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contribution to number theory

...once speculated that at least four fourth powers must be added together for the sum to be a fourth power. But in 1988, using a combination of mathematical insight and computer muscle, the American
Noam Elkies discovered that 2,682,440
4 + 15,365,639
4 + 18,796,760
4 = 20,615,673
4—a stupendous counterexample that...